Westminster is in lockdown, following the stabbing of a police officer within the parliamentary estate. Pedestrians on nearby Westminster Bridge are also reported to have been struck by a car in a related incident. Armed officers shot one suspect. Four people have died, including the police officer and the suspect.

MPs were confined to the chamber or to their offices. A Downing Street source has confirmed that Prime Minister Theresa May is safe.

Commander BJ Harrington from the Metropolitan Police has given a statement, and said this is being treated as a terrorist incident. The Metropolitan Police are asking people to avoid the following areas: Parliament Square, Whitehall, Westminster Bridge, Lambeth Bridge, Victoria Street up to the junction with Broadway, and the Victoria Embankment up to Embankment tube.

An eye witness of the Westminster Bridge incident, Radoslaw Sikorski, posted on Twitter “A car on Westminster Bridge has just mowed down at least 5 people”, along with a video that shows injured people lying in the road. Another witness described the car as going “out of control”.

A junior doctor at St Thomas’ Hospital has reported that one woman has died and others are being treated, including some with “catastrophic” injuries in the incident on Westminster Bridge. A second person is also reported dead. The London Ambulance Service has said its medics have treated at least ten people on Westminster Bridge, and it is reported that at least twenty people have been injured, including three police officers.

Chris Ship of ITV News has reported that a woman has been pulled from the Thames by paramedics. She is thought to have been on Westminster Bridge at the time.

London Ambulance Service deputy director of operations Pauline Cranmer said: “We were called at 2.40pm to Westminster Bridge to reports of an incident.”

The Telegraph’s Ben Riley-Smith reports that Conservative MP and Foreign Office minister Tobias Ellwood gave the stabbed police officer mouth-to-mouth resuscitation and attempted to stem the blood flow from the wounds.

The evacuation from Parliament was at first halted after an announcement that a suspicious package had been found and the bomb squad had been called. Parliamentarians have now been evacuated to the nearby Westminster Abbey and are being briefed.

Westminster station has been evacuated and closed, and the public have been cleared from the area. The London Eye has stopped and is holding all passengers within the attraction. Guy’s and St Thomas’ hospital in Westminster is also in lockdown.